The statements in this section merely provide background information related to the present disclosure and may not constitute prior art.
Recently, eco-friendly vehicles have been rapidly developed in response to concern about environment, and an electric vehicle and a hybrid vehicle are the eco friendly vehicles.
In particular, a hybrid vehicle means a vehicle equipped with a battery and a motor for a driving mode using electric energy and an internal combustion engine for a driving mode like a common vehicle.
When a battery is used to drive a vehicle, such as in a hybrid vehicle, various plans for improving efficiency of electric energy consumption have been proposed. One form is regenerative braking that charges a battery with electric energy produced by transmitting a braking force for deceleration to a motor has drawn attention.
In power-off down-shift in regenerative braking in a hybrid vehicle, braking force by shifting and shifting response varies in accordance with brake pedal effort. To improve drivability, maintaining linearity of the braking force and shifting response is suggested.
Further, when power-off down-shift is started in a vehicle during regenerative braking, the high-efficiency period of a motor for the regenerative braking may not be continued, and the regenerative braking efficiency may decrease.